Peri-operative chemotherapy for muscle-invasive bladder cancer: status-quo in 2017

Introduction

With more than 79,000 new cases and a projection of 16,390 deaths in 2017 in the US (1), bladder cancer is one of the deadliest cancers worldwide. The standard of care for muscle-invasive disease remains radical cystectomy (RC) with pelvic lymph node dissection (PLND), when there is no evidence of metastatic dissemination at initial diagnosis (2). Nonetheless, the 5-year overall survival (OS) rate after such procedure does not exceed 50–60% in expert centers, given that a significant proportion of these patients will ultimately develop fatal recurrences likely due to the presence of occult micrometastases at the time of surgery (3,4).

Striving to improve this paradigm, the efficacy of perioperative chemotherapy has been investigated in multiple landmark randomized controlled trials (RCTs) over the past decades (5,6). Interestingly, although treatment strategies involving the use of either neoadjuvant (NAC) or adjuvant chemotherapy (AC) present substantial limitations, there is a clinical rational for both. Indeed, several meta-analyses support the systematic delivery of NAC for all muscle-invasive bladder cancer (MIBC) patients (7) as well as the selective delivery of AC only in those with adverse pathologic features at RC (8,9). Against this backdrop, the present review aims to summarize the available evidence supporting the use of perioperative chemotherapy associated with RC for localized MIBC to provide a 2017 status-quo.

NAC

Rational

As opposed to AC, the delivery of NAC offers several potential advantages for the management of localized MIBC. First, it is well-established that the better preoperative general condition and renal function of RC patients facilitate the infusion of full-dose cisplatin-based regimens. Second, response to NAC at the time of surgery allows to assess chemosensitivity of the primary tumor. Logically, individuals experiencing downstaging of intravesical disease have a better prognosis than nonresponders (10). In addition, complete pathologic response at RC has been shown to correlate with increased OS in a recent meta-analysis by Petrelli et al. (10). Based on such rational and the proven efficacy of platinum-based regimens for metastatic bladder cancer (11), several landmark RCTs have explored the role of NAC before RC for localized MIBC.

Efficacy

Historical RCTs and meta-analyses

Oncological outcomes from historical RCTs evaluating the role of NAC are heterogeneous. In 1999, the International Collaboration of Trialists published the first large-scale study including 976 patients with cT2-T4N0 bladder cancer to receive either 3 cycles of NAC (cisplatin, methotrexate and vinblastine) (n=491) followed by local treatment or upfront local treatment (n=485) at 106 participating institutions. Despite a benefit in terms of pathological downstaging with the use of NAC, there was no significant difference in OS between the two treatment groups (HR =0.85; 95% CI, 0.71–1.02; P=0.075) after a median follow-up of 4 years (12). The absolute difference in 3-year OS was 5.5% (95% CI, −0.5% to 11%), with corresponding rates of 55.5% in patients who received NAC and 50% in patients who received upfront local treatment. In addition, there was no significant benefit in terms of locoregional disease-free survival (DFS) with the use of NAC (HR =0.87; 95% CI, 0.73–1.02; P=0.087). Nonetheless, the investigators found a significant difference between the two treatments groups with regard to metastasis-free survival (MFS) favoring the use of NAC (HR =0.79; 95% CI, 0.66–0.93; P=0.007); this translated into an absolute difference of 8% (95% CI, 2–14%) in 3-year MFS, with corresponding rates of 53% in the NAC group and 45% in the upfront local treatment group.

Given that other reports showed contradictory results (13,14), the Advanced Bladder Cancer group from the Cochrane collaboration performed a first individual patient data meta-analysis of available RCTs in 2003 (15). After including 2,688 patients from 10 studies, the investigators found that the use of platinum-based NAC was associated with a 13% OS benefit as compared to local treatment alone (HR =0.87; 95% CI, 0.78–0.98; P=0.016); this translated into a 5% absolute benefit (50% vs. 45%, respectively) in 5-year OS. In addition, the use of platinum-based NAC improved significantly DFS (P<0.001) and locoregional DFS (P=0.012) as well as MFS (P=0.001).

However, this first meta-analysis did not include the second largest RCT from the Southwest Oncology Group. Indeed, in 2003, Grossman et al. published the results from a study that randomized 317 patients with cT2-T4a bladder cancer to receive either three cycles of methotrexate, vinblastine, adriamycin and cisplatin (MVAC) followed by RC (n=153) or RC alone (n=154) (3). Interestingly, although patients who received NAC demonstrated higher complete pathologic response rates (38% vs. 15%; P<0.001), there was only a trend toward adverse OS in patients treated with RC alone (HR =1.33; 95% CI, 1.00–1.76). Specifically, the corresponding 5-year rates of OS were 57% in the NAC group and 43% in the RC alone group (P=0.06). Nonetheless, the risk of cancer-specific death was greater in the RC alone group (HR =1.66; 95% CI, 1.22–2.45; P=0.002).

In this context, a second meta-analysis including 3,005 patients from 11 RCTs has been performed by the Advanced Bladder Cancer group from the Cochrane collaboration in 2005 (7). This updated analysis confirmed the OS benefit of platinum-based NAC as compared to local treatment alone (HR =0.86; 95% CI, 0.77–0.95; P=0.003) with an absolute improvement of 5% in 5-year OS. In addition, there was a significant DFS benefit with the use of platinum-based NAC (HR =0.78; 95% CI, 0.71–0.86; P<0.001), with an absolute improvement of 9% in 5-year DFS.

Concomitantly, Winquist et al. conducted a meta-analysis of summary data from 16 RCTs that included 3,315 patients (16). Of these studies, 11 investigators provided data suitable for OS analysis (2,605 patients). The pooled HR was 0.90 (95% CI, 0.82–0.99; P=0.02) overall but, when restricting the analyses to the 8 RCTs including only individuals who received cisplatin-based NAC, the pooled HR was 0.87 (95% CI, 0.78–0.96; P=0.006); this translated into an absolute benefit of 6.5% in 5-year OS with the use of NAC (56.5% vs. 50%). In addition, a major pathological response was associated with improved OS in four included trials.

Additional RCTs and meta-analysis

More recently, three smaller RCTs have been published but only negative results with regard to OS were found by the investigators (17-19). For instance, the Japan Oncology Group analysed 130 patients and found no significant difference in OS between those who received NAC (MVAC) plus RC or RC alone (JCOG0209) (18). However, this study suffered from an early closure due to the slow accrual, which did not allow to reach the initially planned number of included patients. It is noteworthy that a trend toward better OS was observed with the use of NAC (HR =0.65; 95% CI, 0.19–2.18; P=0.07) and the rate of complete pathological response was greater in the NAC followed by RC vs. RC alone group (34% vs. 9%; P<0.01).

Accordingly, an updated meta-analysis of summary data published in 2016 showed a persistent OS benefit with the use of NAC after including all these negative trials (HR =0.87; 95% CI, 0.79–0.96). This benefit was even greater when only considering patients who received cisplatin-based regimen (HR =0.84; 95% CI, 0.76–0.93) (20).

Long-term oncological outcomes

In 2011, the International Collaboration of Trialists evaluated the long-term oncological outcomes of NAC by updating the preliminary results from the previously described historical RCT (4). After a median follow-up of 8 years, there was a significant OS benefit in patients who received NAC as compared to those who received upfront local treatment. Specifically, a 16% reduction in the risk of death from any cause was observed with the use of NAC (HR =0.84; 95% CI, 0.72–0.99; P=0.037); this translated into an increase from 30% to 36% in 10-year OS. In addition, almost all other oncological outcomes were in favour of the use of NAC, given that such treatment was associated with a 23% reduction in the risk of metastases (HR =0.77; 95% CI, 0.66–0.90; P=0.001) and a 18% reduction in the risk of disease recurrence (HR =0.82; 95% CI, 0.70–0.95; P=0.008). Only the DFS benefit associated with the use of NAC was borderline significant (HR =0;83; 95% CI, 0.68–1.00; P=0.050).

Real-life setting

Numerous retrospective reports have confirmed the benefits associated with the use of NAC in the “real-life” setting. For instance, Zargar et al. evaluated pathological downstaging among 935 patients who received NAC followed by RC. Interestingly, the investigators found that the rates of pT0N0 and ¡Ü pT1N0 pathologic response were 22.7% and 40.8%, respectively (21). Other observational studies focused on identifying the best candidates for NAC prior to RC. For instance, Culp et al. proposed a risk-stratified approach for the use of NAC that has recently been validated (22). Specifically, patients were dichotomized in a high- and low-risk groups based on the presence of preoperative risk factors such as ureterohydronephrosis on preoperative CT-scan, lymphovascular invasion, aggressive variant histology, and/or cT3b-T4a disease. Overall, 153 (44.6%) and 190 (55.4%) low- and high-risk patients undergoing RC alone were identified, respectively. At the time of RC, 14.2% of high-risk patients were downstaged. Interestingly, 5-year cancer-specific survival (CSS) rates after surgery were 77.4% vs. 64.4% in the low- and high-risk groups, respectively (23). As such, the present results highlight the interest of selecting individuals who may be more likely to experience tumor downstaging and ultimately benefit from NAC.

In fact, downstaging to ypT0 disease at surgery is of upmost importance given that NAC may be only effective for these patients. Indeed, a recent report by Bhindi et al. has evaluated the impact of residual disease at surgery after matching 180 patients who received NAC plus RC to 324 controls who received RC alone on the basis of pT and pN stages (24). On multivariable analysis, the investigators found that NAC was associated with a DFS, CSS and OS benefit only in patients who experienced ypT0 disease at RC, while such treatment was associated with adverse oncological outcomes in those with residual disease at RC.

Impact of histological variant

To date, no RCT has evaluated the role of NAC for other histologies than pure urothelial carcinoma. As such, it remains unclear whether NAC should be delivered when non-urothelial features are present at initial diagnosis. Only retrospective reports addressing this topic are available in the current literature. One of the largest scale studies has been recently published by Vetterlein et al. (25). Specifically, the investigators compared patients who received NAC followed by RC vs. RC alone for several histological variants including adenocarcinoma, squamous cell carcinoma, micropapillary or sarcomatoid differentiations and neuroendocrine tumors. Although individuals with micropapillary or sarcomatoid differentiations and neuroendocrine tumors experienced a decreased risk of upstaging at RC, only those with neuroendocrine tumors benefited from NAC in terms of OS after adjusting for potential confounding.

Biomarkers for patient selection

It is currently recognized that the systematic delivery of NAC for MIBC may result in substantial overtreatment for a subgroup of patients who could be cured by RC alone. In addition, this may lead to adverse oncological outcomes in chemoresistant individuals by unnecessarily delaying RC. Based on these considerations, several biomarkers predicting the response to NAC have been explored over the past decade to improve the patient selection for such treatment.

Specifically, the classification of MIBC into distinct molecular subtypes could represent one of the most promising methods to identify the best candidates for NAC. To date, four reports developed a similar molecular classification distinguishing between basal and luminal subtypes that are associated with patient outcomes (26-29). In addition, Choi et al. identified a p53-like subtype, mostly within luminal tumours, that could be associated with a limited sensitivity to MVAC regimen in the neoadjuvant setting (27). This resistance pattern to NAC has further been reported for the gemcitabine plus cisplatin (GC) regimen. On the other hand, basal tumours are characterized by high-proliferative indices and could be more responsive to NAC. These results are concordant with the last study published by Seiler et al. who profiled the whole transcriptome of 343 specimens before NAC and subsequently developed a single-sample genomic subtyping classifier (29). The investigators noted that patients with a basal tumor profile had the best response to NAC, confirming that these individuals could represent the best candidates for NAC.

Furthermore, recent immunohistochemistry-based analyses have identified other potential biomarkers associated with response to NAC. For instance, the bladder expression of NrF2, a transcription factor, has been shown to correlate with resistance to cisplatin in vitro and worse OS in patients who received NAC (30). Similarly, the bladder overexpression of Bcl-2, an inhibitor of the apoptotic cascade, could help to identify the nonresponders to NAC (31). Finally, the expression of GDPD3 and SPRED1 has also been shown to correlate with the efficacy of NAC (32).

In addition, genomic assessment could provide interesting information for selecting patients for NAC. Specifically, in vitro analyses showed that missense mutations of ERCC2, a nucleotide excision repair gene, assessed from exome sequencing, may predict response to cisplatin-based NAC. In addition, mutations in ERBB2/HER2 have been shown to correlate with favourable response to NAC (33). More recently, aberrations in DNA repair of ATM, RB1, or FANCC genes have been found to predict pathological response to NAC and could be associated with an improved OS in patients who received NAC (34).

As such, all these studies taken together support the rational for molecular analysis of MIBC to identify biomarkers predictive of clinical response to NAC. However, only heterogeneous and small sample size studies are currently available and as such, none of the aforementioned biomarkers have been validated for clinical practice.

Comparative effectiveness of chemotherapy regimens

To date, no RCT has compared the efficacy of the different chemotherapy regimens in the neoadjuvant setting. Although it is well-established that cisplatin is more effective than carboplatin for treating urothelial carcinoma in general, there is a lack of level 1 evidence in the current literature to determine the best cisplatin-based combination for NAC. Nonetheless, the MVAC regimen could represent a better alternative than GC, given the greater response rates observed in the metastatic setting (35).

As a consequence, only retrospective reports are available to assess the comparative effectiveness of cisplatin-based regimens for NAC. For instance, Dash et al. analysed the oncological outcomes observed after 4 cycles of GC vs. 4 cycles of MVAC (36). The proportions of tumor downstaging and minimal/no residual disease at RC were similar. In addition, there was no substantial difference in DFS, although treatment groups were not directly compared. A recent meta-analysis of all retrospective studies comparing both regimens (including also individuals who received carboplatin instead of cisplatin in combination with gemcitabine) found no significant difference in complete pathological response (20). However, GC/carboplatin was associated with an OS benefit (HR =1.26; 95% CI, 1.01–1.57), which did not reach statistical significance after excluding carboplatin patients (HR =1.31; 95% CI, 0.99–1.74). As such, these results should be interpreted with caution, especially given the substantial biases related to the meta-analyses of retrospective data.

In addition, different modalities for the preoperative delivery of MVAC regimen have been described and analyzed in several phase 2 studies. For instance, Plimack et al. evaluated the oncological outcomes obtained after 3 cycles of accelerated MVAC (aMVAC). It is noteworthy that aMVAC regimen was well tolerated, while rates of pT0 disease after RC were similar to those observed in historical cohorts of patients treated with standard MVAC (37). Comparable results were observed in another study evaluating the efficacy of aMVAC (38). An additional phase 2 RCT of aMVAC with bevacizumab showed 5-year OS and CSS rates of 63% and 64%, respectively. Downstaging to pT0N0 or ¡Ü pT1N0 was observed in 38% and 53% of included patients, respectively. However, bevacizumab was not significantly associated with survival outcomes (39). As such, aMVAC may represent the optimal regimen for NAC but results from several ongoing RCTs comparing different cisplatin-based regimens in the neoadjuvant setting, such as VESPER (NCT01812369), are awaited to draw any definitive conclusion.

AC

Rational

Although the delivery of NAC prior to RC is associated with high rates of pathological downstaging as well as a survival benefit (5), only 1% to 15% of MIBC patients receive such treatment according to the results from population-based studies (40). More recent reports suggest that utilization rates of NAC may be increasing (41,42) but theoretical concerns such as delaying RC while causing unnecessary side effects in chemoresistant patients, represent substantial limitations to the systematic use of NAC. As previously described, multiple biomarkers predicting response to NAC have shown promising results (34,39), but none of them can yet be routinely used for selecting responders with an adequate accuracy. Consequently, a substantial proportion of MIBC patients remains currently chemonaïve at RC and may be suitable for the selective delivery of AC.

The rational for such adjuvant strategy is twofold. First, there is a guarantee that RC is always timely performed without any significant delay that could impact oncological results. Second, the depth of infiltration into the bladder wall, as well as the lymph node status can be accurately determined from the definitive specimen to more adequately guide postoperative treatment decision making. Indeed, it is well-established that pT and pN stages are the most important prognostic factors for both progression and survival after RC (43).

In the late 1980’s, Logothetis et al. first reported that patients who received cisplatin-based AC for pathologically confirmed extravesical and/or pelvic lymph node-positive had greater 2-year DFS than an historic control group of individuals treated with observation after RC (70% vs. 37%; P<0.001) (44). As a result, multiple RCTs have further analyzed the role of AC in this population of patients with high-risk features and several meta-analyses have been conducted to overcome the associated limitations.

Efficacy

Historical RCTs and meta-analyses

The first RCT comparing AC vs. observation after RC for locally advanced bladder cancer was published by Skinner et al. in 1991 (45); they were rapidly followed by others (46,47). However, all these small sample size RCTs suffered from many methodological limitations. Thus, level 1 evidence supporting the use of AC is more contentious than that previously described for the use of NAC.

In 2005, a first meta-analysis of all published RCTs was conducted by the Advanced Bladder Cancer group from the Cochrane collaboration. Interestingly, the systematic review of the literature identified 11 trials but individual patient data were available for only 6 of them (45-50). Although 90% of patients randomized in cisplatin-based AC RCTs were included in this meta-analysis, only 66% of those randomized in all AC RCTs were considered. More importantly, only two of the selected RCTs completed the planned accrual (49,50). In two other RCTs, around a quarter of individuals allocated to AC did not receive such treatment while many AC patients received regimens other than those described in the study protocol (46,48). Finally, four included RCTs did not report on the use of salvage chemotherapy for disease recurrence in the group of patients who received initial observation (45-47,49), with a likely consequence of exaggerating the treatment effect of AC.

In spite of these limitations, this pioneering meta-analysis identified an OS benefit in favor of AC vs. observation (HR =0.75; 95% CI, 0.60–0.96; P=0.019), which was more pronounced in the sub-group of patients who received cisplatin-based AC (HR =0.71; 95% CI, 0.55–0.92; P=0.010). This corresponded to an absolute improvement in 3-year OS of 9% (95% CI, 1%–16%), which extended to 11% (95% CI, 3%–18%) when considering exclusively cisplatin-based AC. In addition, the use of AC was associated with a DFS benefit (HR =0.68; 95% CI, 0.53–0.89; P=0.004), which was also more pronounced when only considering patients who received cisplatin-based AC (HR =0.62; 95% CI, 0.46–0.83; P=0.001).

Another meta-analysis of summary data from all published RCTs was undertaken by Ruggeri et al. in 2006 (51). The investigators found similar results than those reported in the aforementioned meta-analysis based on individual patient data. Specifically, AC was associated with a 26% and 35% reduction in the risk of death from any cause (RR =0.74; 95% CI, 0.62–0.88; P=0.001) and disease recurrence (RR =0.65; 95% CI, 0.54–0.78; P<0.001), respectively.

Nonetheless, other RCTs were conducted (52-54) and further included in an updated systematic review and meta-analysis of summary data published in 2013 (9). In this report, Leow et al. built on the 2005 meta-analysis by the Advanced Bladder Cancer group from the Cochrane collaboration to additionally consider the Italian multicenter study (52), the Spanish Oncologic Genito-Urinary Group (SOGUG) study (53), and the US p53 Intergroup study (54). In addition, the update of the 1994 Stöckle RCT (46) published by Lehmann et al. in 2006 with a 10-year follow-up after RC (55) was considered by the investigators, who ultimately identified a 23% and 34% reduction in the risk of death from any cause (HR =0.77; 95% CI, 0.59–0.99; P=0.049) and disease recurrence (HR =0.66; 95% CI, 0.45–0.91; P=0.014), respectively. The treatment estimate was more pronounced for both OS (HR =0.74; 95% CI, 0.58–0.94) and DFS (HR =0.62; 95% CI, 0.45–0.87), when considering exclusively cisplatin-based AC. This updated meta-analysis remained limited in terms of sample size with approximately 950 included patients and suffered from the same aforementioned methodological issues inherent to the inclusion of potentially biased RCTs. Thus, the results from the very last RCT by the European Organization for Research and Treatment of Cancer (EORTC) comparing adjuvant vs. deferred chemotherapy were largely awaited to potentially fill the gap of rigorous level 1 evidence (6).

EORTC 30994 RCT

The EORTC 30994 is the largest phase 3 RCT comparing adjuvant vs. delayed chemotherapy (6). Nonetheless, only 284 patients, of the 660 initially planned, with pT3/T4 and/or pN+ bladder cancer were enrolled to randomly receive either adjuvant (n=141) or deferred (n=143) chemotherapy. After a median follow-up of 7 years, 66 (47%) and 82 (57%) patients died in the adjuvant and deferred chemotherapy groups, respectively. Although there was no significant benefit of AC in terms of OS (HR =0.78; 95% CI, 0.56–1.08; P=0.13), such treatment was associated with prolonged progression-free survival (PFS) as compared to the delivery of chemotherapy at the time of relapse (HR =0.54; 95% CI, 0.40–0.73; P<0.001). This corresponded to an absolute improvement of approximately 16% in 5-year PFS. In post-hoc analyses, Sternberg et al. identified a significant interaction between pN stage and the treatment effect of AC on OS (pN− vs. pN+; P_interaction=0.026). Surprisingly, the benefit of AC remained significant only in patients without lymph node involvement at initial diagnosis (HR =0.37; 95% CI, 0.16–0.83; P=0.012), while no difference was noted with the deferred chemotherapy group in those with pelvic lymph node-positive bladder cancer (HR =0.94; 95% CI, 0.65–1.34; P<0.72). In addition, the investigators conducted an updated meta-analysis building on the aforementioned Leow’s report (9) and identified an OS benefit (HR =0.77; 95% CI, 0.65–0.91; P=0.001) with the use of AC, which was borderline significant when restricting the inclusion to the Italian, Spanish, and EORTC studies (HR =0.79; 95% CI, 0.62–1.00; P=0.05).

Real-life setting

Given that all these RCTs share the common pattern of incomplete accrual with limited adherence to the treatment protocol, several contemporary retrospective studies have been published with the aim to overcome the underpowered level 1 evidence (56). Unfortunately, these observational reports comparing AC vs. observation after RC are likely to be limited by other methodological issues such as selection bias in treatment allocation.

Nonetheless, a collaborative effort among 11 major centers has yielded an international cohort of 3,947 off-trial patients treated with RC and grouped into quintiles based on risk characteristics for recurrence and death (57). Of these, 932 (23.6%) individuals received AC, which was independently associated with improved CSS (HR =0.83; 95% CI, 0.72%–0.97%; P=0.017). Interestingly, risk groups significantly predicted the magnitude of the treatment effect of AC, given that a greater benefit was observed among patients with more aggressive disease. Specifically, the CSS benefit was only significant in the highest-risk quintile (HR =0.75; 95% CI, 0.62–0.90; P=0.002), which was characterized by the inclusion of a large majority of patients displaying both pT3/T4 and pN+ features at RC.

More recently, a retrospective analysis of 5,653 patients from the National Cancer Data Base (NCDB) who received AC vs. observation after RC for pT3/T4 and/or pN+ bladder cancer was published by Galsky et al. (58). To date, this is the largest series available with almost 1,300 patients who received AC that was associated with an OS benefit. Specifically, after using several propensity score-based analyses to adjust for baseline patient-, facility- and disease-level characteristics, individuals who received AC were 30% less likely to die following RC as compared to their counterparts who received observation (HR =0.70; 95% CI, 0.64–0.76). This corresponded to an absolute increase of 8% in 5-year OS.

In order to assess the potential benefit of AC, other sophisticated statistical approaches have been used to compare patients who received AC vs. observation. For instance, Vetterlein et al. performed a propensity-score weighted competing risk analysis showing that AC decreased the risk of cancer-specific mortality (subhazard ratio =0.51, 95% CI, 0.26–0.98; P=0.044) without increasing the risk of other-cause mortality (subhazard ratio =0.48, 95% CI, 0.14–1.60; P=0.233) (59). Similar results were found in the study by Froehner et al. (60).

It is noteworthy that observational studies also identified that patients benefiting the most from AC may be those with a low lymph node density as well as those who can receive at least 4 cycles of treatment (61). In addition, PLND at the time of RC has been shown to constitute an important component of advanced bladder cancer management, which could help with regard to indications for AC (62).

Comparative effectiveness of chemotherapy regimens

The GC regimen is preferentially used over the MVAC combination for AC. This is largely based on the results from the RCT by von der Maase et al. showing no OS benefit with a regimen over the other for the treatment of advanced or metastatic bladder cancer, and a better toxicity profile for the GC regimen (35). Nonetheless, there is currently no level 1 evidence comparing these 2 regimens in the adjuvant setting. Only retrospective studies suggesting no significant difference in terms of recurrence and survival are currently available (63). Although it is well-established that carboplatin represents a suboptimal treatment for advanced urothelial disease in general, there is insufficient evidence to determine the optimal cisplatin-based AC regimen (64). Nonetheless, in the same manner than for NAC, several ongoing RCTs such as VESPER (NCT01812369) could provide additional guidance in the upcoming years.

Role of AC after NAC and RC

To date, there is no level 1 evidence supporting the use of AC for adverse pathological features at RC despite the delivery of NAC before undergoing surgery, given that all the aforementioned RCTs excluded these patients. However, a small sample size observational study including only 80 patients with pT3/T4 and/or pN+ bladder cancer—29 of whom received AC—found no DFS or CSS benefit with the use of AC in such setting (65). Nonetheless, more recently, a larger NCDB report addressing this topic was published by Seisen et al. (66). The investigators identified 788 patients who received either AC (n=184) or observation (n=604) for the same adverse pathological features at RC after NAC. Interestingly, the use of AC was associated with an OS benefit (HR =0.78, 95% CI, 0.95–0.99, P=0.046), although the study was limited by several missing data, such as the detailed chemotherapy regimen or the number/completeness of chemotherapy cycles administered at the time of NAC and AC.

Conclusions

The current literature largely supports the use of NAC before performing RC for MIBC. However, patient selection for such treatment is challenging given that no biomarker predicting the response to NAC can yet be routinely used. On the other hand, evidence supporting the use of AC after RC is more contentious but there is a consensus that it should be proposed to fit patients with adverse pathological features at surgery. While the most effective regimen still remains to be determined for both NAC and AC, the therapeutic landscape for perioperative management of MIBC could dramatically change in a near future, given the recent advent of immune check-point inhibitors for metastatic disease.

Acknowledgements

None.

Footnote

Conflicts of Interest: The authors have no conflicts of interest to declare.

References

1. Siegel RL, Miller KD, Jemal A. Cancer Statistics, 2017. CA Cancer J Clin 2017;67:7-30. [Crossref] [PubMed]
2. Alfred Witjes J, Lebret T, Compérat EM, et al. Updated 2016 EAU Guidelines on Muscle-invasive and Metastatic Bladder Cancer. Eur Urol 2017;71:462-75. [Crossref] [PubMed]
3. Grossman HB, Natale RB, Tangen CM, et al. Neoadjuvant chemotherapy plus cystectomy compared with cystectomy alone for locally advanced bladder cancer. N Engl J Med 2003;349:859-66. [Crossref] [PubMed]
4. Madersbacher S, Hochreiter W, Burkhard F, et al. Radical cystectomy for bladder cancer today--a homogeneous series without neoadjuvant therapy. J Clin Oncol 2003;21:690-6. [Crossref] [PubMed]
5. International Collaboration of Trialists; Medical Research Council Advanced Bladder Cancer Working Party. International phase III trial assessing neoadjuvant cisplatin, methotrexate, and vinblastine chemotherapy for muscle-invasive bladder cancer: long-term results of the BA06 30894 trial. J Clin Oncol 2011;29:2171-7. [Crossref] [PubMed]
6. Sternberg CN, Skoneczna I, Kerst JM, et al. Immediate Versus Deferred Chemotherapy After Radical Cystectomy in Patients with pT3-pT4 or N+ M0 Urothelial Carcinoma of the Bladder (EORTC 30994): An Intergroup, Open-label, Randomised Phase 3 Trial. Lancet Oncol 2015;16:76-86. [Crossref] [PubMed]
7. Advanced Bladder Cancer Overview Collaboration. Neoadjuvant chemotherapy for invasive bladder cancer. Cochrane Database Syst Rev 2005.CD005246. [PubMed]
8. Advanced Bladder Cancer (ABC) Meta-analysis Collaboration. Adjuvant chemotherapy for invasive bladder cancer (individual patient data). Cochrane Database Syst Rev 2006.CD006018. [PubMed]
9. Leow JJ, Martin-Doyle W, Rajagopal PS, et al. Adjuvant chemotherapy for invasive bladder cancer: a 2013 updated systematic review and meta-analysis of randomized trials. Eur Urol 2014;66:42-54. [Crossref] [PubMed]
10. Petrelli F, Coinu A, Cabiddu M, et al. Correlation of pathologic complete response with survival after neoadjuvant chemotherapy in bladder cancer treated with cystectomy: a meta-analysis. Eur Urol 2014;65:350-7. [Crossref] [PubMed]
11. Mead GM, Russell M, Clark P, et al. A randomized trial comparing methotrexate and vinblastine (MV) with cisplatin, methotrexate and vinblastine (CMV) in advanced transitional cell carcinoma: results and a report on prognostic factors in a Medical Research Council study. MRC Advanced Bladder Cancer Working Party. Br J Cancer 1998;78:1067-75. [Crossref] [PubMed]
12. Neoadjuvant cisplatin, methotrexate, and vinblastine chemotherapy for muscle-invasive bladder cancer: a randomised controlled trial. International collaboration of trialists. Lancet 1999;354:533-40. [Crossref] [PubMed]
13. Sengeløv L, von der Maase H, Lundbeck F, et al. Neoadjuvant chemotherapy with cisplatin and methotrexate in patients with muscle-invasive bladder tumours. Acta Oncol 2002;41:447-56. [Crossref] [PubMed]
14. Malmström PU, Rintala E, Wahlqvist R, et al. Five-year followup of a prospective trial of radical cystectomy and neoadjuvant chemotherapy: Nordic Cystectomy Trial I. The Nordic Cooperative Bladder Cancer Study Group. J Urol 1996;155:1903-6. [Crossref] [PubMed]
15. Advanced Bladder Cancer Meta-analysis Collaboration. Neoadjuvant chemotherapy in invasive bladder cancer: a systematic review and meta-analysis. Lancet 2003;361:1927-34. [Crossref] [PubMed]
16. Winquist E, Kirchner TS, Segal R, et al. Neoadjuvant chemotherapy for transitional cell carcinoma of the bladder: a systematic review and meta-analysis. J Urol 2004;171:561-9. [Crossref] [PubMed]
17. Osman MA, Gabr AM, Elkady MS. Neoadjuvant chemotherapy versus cystectomy in management of stages II, and III urinary bladder cancer. Arch Ital Urol Androl 2014;86:278-83. [Crossref] [PubMed]
18. Kitamura H, Tsukamoto T, Shibata T, et al. Randomised phase III study of neoadjuvant chemotherapy with methotrexate, doxorubicin, vinblastine and cisplatin followed by radical cystectomy compared with radical cystectomy alone for muscle-invasive bladder cancer: Japan Clinical Oncology Group Study JCOG0209. Ann Oncol 2014;25:1192-8. [Crossref] [PubMed]
19. Khaled HM, Shafik HE, Zabhloul MS, et al. Gemcitabine and cisplatin as neoadjuvant chemotherapy for invasive transitional and squamous cell carcinoma of the bladder: effect on survival and bladder preservation. Clin Genitourin Cancer 2014;12:e233-40. [Crossref] [PubMed]
20. Yin M, Joshi M, Meijer RP, et al. Neoadjuvant Chemotherapy for Muscle-Invasive Bladder Cancer: A Systematic Review and Two-Step Meta-Analysis. Oncologist 2016;21:708-15. [Crossref] [PubMed]
21. Zargar H, Espiritu PN, Fairey AS, et al. Multicenter assessment of neoadjuvant chemotherapy for muscle-invasive bladder cancer. Eur Urol 2015;67:241-9. [Crossref] [PubMed]
22. Culp SH, Dickstein RJ, Grossman HB, et al. Refining patient selection for neoadjuvant chemotherapy before radical cystectomy. J Urol 2014;191:40-7. [Crossref] [PubMed]
23. Moschini M, Soria F, Klatte T, et al. Validation of Preoperative Risk Grouping of the Selection of Patients Most Likely to Benefit From Neoadjuvant Chemotherapy Before Radical Cystectomy. Clin Genitourin Cancer 2017;15:e267-73. [Crossref] [PubMed]
24. Bhindi B, Frank I, Mason RJ, et al. Oncologic Outcomes for Patients with Residual Cancer at Cystectomy Following Neoadjuvant Chemotherapy: A Pathologic Stage-matched Analysis. Eur Urol 2017;72:660-4. [Crossref] [PubMed]
25. Vetterlein MW, Wankowicz SAM, Seisen T, et al. Neoadjuvant chemotherapy prior to radical cystectomy for muscle-invasive bladder cancer with variant histology. Cancer 2017;123:4346-55. [Crossref] [PubMed]
26. Damrauer JS, Hoadley KA, Chism DD, et al. Intrinsic subtypes of high-grade bladder cancer reflect the hallmarks of breast cancer biology. Proc Natl Acad Sci U S A 2014;111:3110-5. [Crossref] [PubMed]
27. Choi W, Porten S, Kim S, et al. Identification of distinct basal and luminal subtypes of muscle-invasive bladder cancer with different sensitivities to frontline chemotherapy. Cancer Cell 2014;25:152-65. [Crossref] [PubMed]
28. Sjödahl G, Lauss M, Lövgren K, et al. A molecular taxonomy for urothelial carcinoma. Clin Cancer Res 2012;18:3377-86. [Crossref] [PubMed]
29. Seiler R, Ashab HAD, Erho N, et al. Impact of Molecular Subtypes in Muscle-invasive Bladder Cancer on Predicting Response and Survival after Neoadjuvant Chemotherapy. Eur Urol 2017;72:544-54. [Crossref] [PubMed]
30. Hayden A, Douglas J, Sommerlad M, et al. The Nrf2 transcription factor contributes to resistance to cisplatin in bladder cancer. Urol Oncol 2014;32:806-14. [Crossref] [PubMed]
31. Kiss B, Skuginna V, Fleischmann A, et al. Bcl-2 predicts response to neoadjuvant chemotherapy and is overexpressed in lymph node metastases of urothelial cancer of the bladder. Urol Oncol 2015;33:166.e1-8. [Crossref] [PubMed]
32. Baras AS, Gandhi N, Munari E, et al. Identification and Validation of Protein Biomarkers of Response to Neoadjuvant Platinum Chemotherapy in Muscle Invasive Urothelial Carcinoma. PLoS One 2015;10:e0131245. [Crossref] [PubMed]
33. Van Allen EM, Mouw KW, Kim P, et al. Somatic ERCC2 mutations correlate with cisplatin sensitivity in muscle-invasive urothelial carcinoma. Cancer Discov 2014;4:1140-53. [Crossref] [PubMed]
34. Plimack ER, Dunbrack RL, Brennan TA, et al. Defects in DNA Repair Genes Predict Response to Neoadjuvant Cisplatin-based Chemotherapy in Muscle-invasive Bladder Cancer. Eur Urol 2015;68:959-67. [Crossref] [PubMed]
35. von der Maase H, Hansen SW, Roberts JT, et al. Gemcitabine and cisplatin versus methotrexate, vinblastine, doxorubicin, and cisplatin in advanced or metastatic bladder cancer: results of a large, randomized, multinational, multicenter, phase III study. J Clin Oncol 2000;18:3068-77. [Crossref] [PubMed]
36. Dash A, Pettus JA 4th, Herr HW, et al. A role for neoadjuvant gemcitabine plus cisplatin in muscle-invasive urothelial carcinoma of the bladder: a retrospective experience. Cancer 2008;113:2471-7. [Crossref] [PubMed]
37. Plimack ER, Hoffman-Censits JH, Viterbo R, et al. Accelerated methotrexate, vinblastine, doxorubicin, and cisplatin is safe, effective, and efficient neoadjuvant treatment for muscle-invasive bladder cancer: results of a multicenter phase II study with molecular correlates of response and toxicity. J Clin Oncol 2014;32:1895-901. [Crossref] [PubMed]
38. Choueiri TK, Jacobus S, Bellmunt J, et al. Neoadjuvant dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin with pegfilgrastim support in muscle-invasive urothelial cancer: pathologic, radiologic, and biomarker correlates. J Clin Oncol 2014;32:1889-94. [Crossref] [PubMed]
39. McConkey DJ, Choi W, Shen Y, et al. A Prognostic Gene Expression Signature in the Molecular Classification of Chemotherapy-naïve Urothelial Cancer is Predictive of Clinical Outcomes from Neoadjuvant Chemotherapy: A Phase 2 Trial of Dose-dense Methotrexate, Vinblastine, Doxorubicin, and Cisplatin with Bevacizumab in Urothelial Cancer. Eur Urol 2016;69:855-62. [Crossref] [PubMed]
40. David KA, Milowsky MI, Ritchey J, et al. Low incidence of perioperative chemotherapy for stage III bladder cancer 1998 to 2003: a report from the National Cancer Data Base. J Urol 2007;178:451-4. [Crossref] [PubMed]
41. Booth CM, Siemens DR, Peng Y, et al. Delivery of perioperative chemotherapy for bladder cancer in routine clinical practice. Ann Oncol 2014;25:1783-8. [Crossref] [PubMed]
42. Reardon ZD, Patel SG, Zaid HB, et al. Trends in the use of perioperative chemotherapy for localized and locally advanced muscle-invasive bladder cancer: a sign of changing tides. Eur Urol 2015;67:165-70. [Crossref] [PubMed]
43. Stein JP, Lieskovsky G, Cote R, et al. Radical cystectomy in the treatment of invasive bladder cancer: long-term results in 1,054 patients. J Clin Oncol 2001;19:666-75. [Crossref] [PubMed]
44. Logothetis CJ, Johnson DE, Chong C, et al. Adjuvant cyclophosphamide, doxorubicin, and cisplatin chemotherapy for bladder cancer: an update. J Clin Oncol 1988;6:1590-6. [Crossref] [PubMed]
45. Skinner DG, Daniels JR, Russell CA, et al. The role of adjuvant chemotherapy following cystectomy for invasive bladder cancer: a prospective comparative trial. J Urol 1991;145:459-64; discussion 464-7. [Crossref] [PubMed]
46. Stöckle M, Meyenburg W, Wellek S, et al. Adjuvant polychemotherapy of nonorgan-confined bladder cancer after radical cystectomy revisited: long-term results of a controlled prospective study and further clinical experience. J Urol 1995;153:47-52. [Crossref] [PubMed]
47. Freiha F, Reese J, Torti FM. A randomized trial of radical cystectomy versus radical cystectomy plus cisplatin, vinblastine and methotrexate chemotherapy for muscle invasive bladder cancer. J Urol 1996;155:495-9; discussion 499-500. [Crossref] [PubMed]
48. Studer UE, Bacchi M, Biedermann C, et al. Adjuvant cisplatin chemotherapy following cystectomy for bladder cancer: results of a prospective randomized trial. J Urol 1994;152:81-4. [Crossref] [PubMed]
49. Bono AV, Benvenuti C, Gibba A, et al. Adjuvant chemotherapy in locally advanced bladder cancer. Final analysis of a controlled multicentre study. Acta Urol Ital 1997;11:5-8.
50. Otto T, Goebell PJ, Rübben H. Perioperative Chemotherapy in Advanced Bladder Cancer - Part II: Adjuvant Treatment. Onkologie 2003;26:484-8. [PubMed]
51. Ruggeri EM, Giannarelli D, Bria E, et al. Adjuvant chemotherapy in muscle-invasive bladder carcinoma: a pooled analysis from phase III studies. Cancer 2006;106:783-8. [Crossref] [PubMed]
52. Cognetti F, Ruggeri EM, Felici A, et al. Adjuvant chemotherapy with cisplatin and gemcitabine versus chemotherapy at relapse in patients with muscle-invasive bladder cancer submitted to radical cystectomy: an Italian, multicenter, randomized phase III trial. Ann Oncol 2012;23:695-700. [Crossref] [PubMed]
53. Paz-Ares LG, Solsona E, Esteban E, et al. Randomized phase III trial comparing adjuvant paclitaxel/gemcitabine/cisplatin (PGC) to observation in patients with resected invasive bladder cancer: results of the Spanish Oncology Genitourinary Group (SOGUG) 99/01study. J Clin Oncol 2010;28:abstr LBA4518.
54. Stadler WM, Lerner SP, Groshen S, et al. Phase III study of molecularly targeted adjuvant therapy in locally advanced urothelial cancer of the bladder based on p53 status. J Clin Oncol 2011;29:3443-9. [Crossref] [PubMed]
55. Lehmann J, Franzaring L, Thüroff J, et al. Complete long-term survival data from a trial of adjuvant chemotherapy vs control after radical cystectomy for locally advanced bladder cancer. BJU Int 2006;97:42-7. [Crossref] [PubMed]
56. Lucca I, Rouprêt M, Kluth L, et al. Adjuvant cisplatin-based combined chemotherapy for lymph node (LN)-positive urothelial carcinoma of the bladder (UCB) after radical cystectomy (RC): a retrospective international study of >1500 patients. BJU Int 2015;115:722-7. [Crossref] [PubMed]
57. Svatek RS, Shariat SF, Lasky RE, et al. The effectiveness of off-protocol adjuvant chemotherapy for patients with urothelial carcinoma of the urinary bladder. Clin Cancer Res 2010;16:4461-7. [Crossref] [PubMed]
58. Galsky MD, Stensland KD, Moshier E, et al. Effectiveness of Adjuvant Chemotherapy for Locally Advanced Bladder Cancer. J Clin Oncol 2016;34:825-32. [Crossref] [PubMed]
59. Vetterlein MW, Seisen T, May M, et al. Effectiveness of Adjuvant Chemotherapy After Radical Cystectomy for Locally Advanced and/or Pelvic Lymph Node-Positive Muscle-invasive Urothelial Carcinoma of the Bladder: A Propensity Score-Weighted Competing Risks Analysis. Eur Urol Focus 2016. [Epub ahead of print]. [Crossref] [PubMed]
60. Froehner M, Koch R, Heberling U, et al. Decreased Overall and Bladder Cancer-Specific Mortality with Adjuvant Chemotherapy After Radical Cystectomy: Multivariable Competing Risk Analysis. Eur Urol 2016;69:984-7. [Crossref] [PubMed]
61. Pouessel D, Bastuji-Garin S, Houédé N, et al. Adjuvant Chemotherapy After Radical Cystectomy for Urothelial Bladder Cancer: Outcome and Prognostic Factors for Survival in a French Multicenter, Contemporary Cohort. Clin Genitourin Cancer 2017;15:e45-e52. [Crossref] [PubMed]
62. Boström PJ, Mirtti T, van Rhijn B, et al. Benefit of Adjuvant Chemotherapy and Pelvic Lymph Node Dissection in pT3 and Node Positive Bladder Cancer Patients Treated with Radical Cystectomy. Bladder Cancer 2016;2:263-72. [Crossref] [PubMed]
63. Dorff TB, Tsao-Wei D, Miranda G, et al. Adjuvant chemotherapy for locally advanced urothelial carcinoma: an overview of the USC experience. World J Urol 2009;27:39-44. [Crossref] [PubMed]
64. Chou R, Selph SS, Buckley DI, et al. Treatment of muscle-invasive bladder cancer: A systematic review. Cancer 2016;122:842-51. [Crossref] [PubMed]
65. Zargar-Shoshtari K, Kongnyuy M, Sharma P, et al. Clinical role of additional adjuvant chemotherapy in patients with locally advanced urothelial carcinoma following neoadjuvant chemotherapy and cystectomy. World J Urol 2016;34:1567-73. [Crossref] [PubMed]
66. Seisen T, Jamzadeh A, Leow JJ, et al. Adjuvant chemotherapy vs observation for patients with adverse pathological features at radical cystectomy previously treated with neoadjuvant chemotherapy. JAMA Oncol 2017. [Epub ahead of print]. [Crossref] [PubMed]